Ethernet Virtual Private Network (E-VPN) is a layer 2 virtual private network (VPN) technology, and is based on Multiprotocol Label Switching (MPLS). Internet Protocol VPN (IP-VPN) is a layer 3 VPN technology which is generally also based on MPLS.
In many networks, soft switches which run on a virtual machine (VM) or a hypervisor hosted on a server are used to provide efficient intra-server inter-virtual machine switching, flexibility, and ease of provisioning as a part of server orchestration. Servers on which soft switches run on a VM or a hypervisor are multi-homed to Top-of-Rack (ToR) switches using multi-chassis link aggregation groups (LAGs).
Some ToR switches offer layer 3 connectivity to associated, e.g., attached, servers. Although layer 3 connectivity generally allows intra-subnet and inter-subnet traffic to be forwarded, the use of layer 3 connectivity to support intra-subnet and inter-submit traffic forwarding may be inefficient and may cause issues which impact the performance of a network. By way of example, unknown Internet Protocol (IP) destination addresses may be dropped with layer 3 forwarding, media access control (MAC) addresses of originating hosts may be set to addresses of Network Virtualize Endpoints (NVEs), an IP time-to-live (TTL) may be decremented thereby causing applications which confine traffic by setting an IP TTL to a value of one to no longer function, and/or mechanisms which rely on layer 2 connectivity may no longer function as expected.